The AC adapter's job is to take standard household AC, reduce the voltage, and convert it to tightly-regulated direct current (DC) that electronic appliances need. These appliances and their rechargeable batteries cannot use AC directly.
AC: For example, in the United States, it is typical that the electricity in your household wiring comes as 110-127 volts of 60-cycle alternating current. The AC adapter plugs into a standard outlet and feeds this AC into a small transformer. At any given moment, the average American house has 120 volts of electricity flowing through it. All of Europe and most of South America, Africa and Asia, as well as Australia and New Zealand use a supply that is within 10% of 230 V, whereas Japan, North America and some parts of northern South America use a voltage between 100 and 127 V. In general, most of the world uses the 230 V standard. This also means that standard 230 V equipment can be used in most parts of the world, with only a minor change in the equipment's electrical plug for a specific country.
Transformer: The transformer, a pair of wire coils wound on an iron frame, efficiently drops the voltage from 110 to a more useful level, such as 9 volts. Though the voltage is lower, it remains AC and needs further steps before your gadgets can use it.
Rectifier: A set of two or four diodes, connected to form a rectifier, changes the low-voltage AC to DC. This electricity, while more useful, has too much noise to power sensitive electronics.
Regulator: The adapter has a regulator circuit that holds the rectified DC to a very steady level. The voltage stays the same despite changes in the appliance's power consumption. This steady, clean DC power keeps complex electronic gadgets reliable.
Many adapters can be used in different countries. For example, the Toshiba Global AC Adapter can be used with select Toshiba notebooks. The universal 100/240 power input means one can use the AC adapter around the world with an appropriate plug adapter for whatever region he/she is traveling to.
U.S. Pat. No. 7,224,086 to Germagian et al. discloses a “Universal Multiple Device Power Adapter and Carry Case.”
The main purpose of this device is for electronics to be charged through the convenience of a bag without all the cords. The power distributor that connects multiple devices has multiple ports to accommodate powering of more than two additional devices. Cords connected to the power distributor can have integrated DC/DC converters for creating any desired voltage level. However this device powers many different electronic devices, and still uses many cords in the process. Your Multiple Laptop Power Cord would be specific to standard three prong plug-in devices, such as laptops and the plug would be integrated into the voltage adapter box on the laptop cord, eliminating any excess cords.
U.S. Pat. No. 6,172,891 to O'Neal et al. discloses an “AC Voltage adapter with integrated DC Voltage Power Supply Connector.” Here, the first connector “120” provides for connecting to a DC voltage operable device and the second connector “126” provides for connecting to a remote DC voltage power supply. This is not the same as your device which will plug in multiple DC voltage operable devices.
U.S. Pat. No. 5,602,455 to Stephens et al. discloses a “Portable Battery Charger with Integrally Attached Output Cable.”
Here, the device charges internal and external laptop batteries at the same time. This is not the same as your device which will power two laptops simultaneously.
The prior art includes adapters without the capability for other devices to plug into the adapter.
There exists a need for an adapter capable of receiving power cords, both two prong and three prong.
There also exists a need for an adapter that has a rechargeable and replaceable battery.
Multiple embodiments of the system are disclosed herein. It will be understood that other objects and purposes of the invention, and variations thereof, will be apparent upon reading the following specification and inspecting the accompanying drawings.